Over the years, a multitude of shoe designs have been advanced with varying regard to style, comfort, and utility. Certainly, in some instances, utilitarian considerations have been almost totally disregarded in favor of style. As a related aspect, the structural features of a shoe are not always compatible in providing comfort while supporting the foot for movement. That is, a rather comfortable shoe may well impede the wearer in moving effectively or its use may be physically detrimental to the foot, leg, or back.
In recent years, considerable emphasis has been placed on the development of improved shoes for various athletic activities. In that regard, a number of specialized shoes have been developed and somewhat concurrently, a variety of structures have been proposed for incorporation in such shoes. For example, it has been proposed to provide coil springs in the platforms of shoes, as disclosed for example in U.S. Pat. Nos. 2,274,890 (Cunningham); 2,299,009 (Denk); 2,710,460 (Stasinos); 2,721,400 (Israel); and 4,030,213 (Daswick).
Another structural feature that previously has been proposed for shoes involves the incorporation of an air chamber in the platform of a shoe as to cushion the foot. Examples of such U.S. Pat. Nos. are: 4,008,530 (Gager); 4,012,854 (Berend et al); and 4,016,662 (Thompson).
Over the years, various other structures and forms have been proposed for use in shoes, both for special purposes and general use. However, in general a need continues to exist for a truly effective biomechanical shoe which can be economically produced for effective use.
In general, the present invention is directed to a biomechanical shoe which may be embodied in various embodiments, as for athletic use. The overall function of the shoe, as disclosed herein, is to enhance the normal foot and leg motion while running and to decrease abnormal motions. However, the shoe of the present invention may also be embodied in forms which conform to existing style requirements. Structurally, the shoe of the present invention incorporates a controlled-spring cushion platform which receives an upper incorporating a heel cup, which may take the form of a dynamic pneumatic cushion. At the forward insole of the shoe, a ridge or elevated area is provided to mate with the sulcus, affording improved action for the toes and related muscles of the foot.